The offensive line was by far the most consistent unit of the 2009/2010 New England Patriots. Left tackle Matt Light, left guard Logan Mankins, center Dan Koppen, right guard Stephen Neal, and right Tackle Nick Kaczur allowed opposing defenses very few cracks at three-time Super Bowl champion quarterback Tom Brady. Brady –unfortunate to sustain nagging injuries to his fingers and ribs, was sacked just 16 times last season–the fewest sacks allowed by a Patriots line since the NFL moved to a 16-game schedule.

Here’s what Brady had to say about the offensive line last August:

“I think we have a great offensive line…It’s a very veteran offensive line that’s been together for a while. [Koppen] leads that group standing in the middle of two guys on each side. It’s a very athletic group that works hard and is very well coached. Dante is one of the best offensive coaches in the league. They always provide great protection. It’s a smart group, a tough group. They’re always out there. I look forward to being back behind them.”

Matt Light (left tackle)

2009 marked the fifth consecutive season these five players have started together. All five were either drafted by the Patriots or signed as undrafted free agents, and they’ve developed a strong sense of familiarity with one another. However, there might be a few new faces on this line by the beginning of this coming season. Light, whose been anchoring the left side of the line since he was drafted by the Pats in 2001, could either be traded, or simply lose his starting position to bright young talent Sebastian Vollmer. At 6 ft. 7, with graceful feet, Vollmer is the team’s left tackle of the future. Thus, it appears Light’s days in Foxboro are numbered. Certainly, both Light’s health and level of play have declined over the past couple years. The 31-year-old veteran is due to make $4.5 million this year, the final year of his contract. So, it wouldn’t be shocking to see him starting somewhere else in September.

Whether or not Logan Mankins stays will have a big impact on Light’s future with the team. If Mankins leaves, they’ll probably just slide Kaczur over to left guard and use Vollmer at right tackle, and line-up. However if he stays, Light could be on the hot seat with Vollmer waiting in the wings.

“At this point, I’m pretty frustrated, from everything that’s happened and the way negotiations have gone,” Mankins said in a phone interview. “I want to be traded. I don’t need to be here any more.”

Details surrounding Mankins’ financial negotiations with the team have yet to be fully brought to light. His agent, Frank Bauer, claims the offer made by the Patriots is 20 percent lower than the amount offered to Jahri Evans by the Saints. Rules set in place by the NFL for the uncapped year prevented Mankins from becoming an unrestricted free agent. The Patriots now have the right to reduce their offer from $3.26 million to $1.54 million.

There will be a huge hole to fill if the Patriots can’t bring back Mankins 2010. The first-round pick made it to his second Pro Bowl last season, and is widely regarded as one of the best guards in the game today. Mankins’ discontent is also worrisome because the Pats drafted just one offensive lineman in April, Tackle Thomas Welch of Vanderbilt (7th round). Dan Connolly, who the Patriots signed to their practice squad in 2007, is the team’s top backup interior lineman.

Dan Koppen (center)

Drafted out of Boston College by the Pats in 2003, Dan Koppen has developed into one of the best young centers in the NFL. Koppen was thrown into the fire early in his career when he filled in for the injured Damien Woody in 2004, the same year the Patriots went on to win Super Bowl XXXVIII over the Carolina Panthers. Koppen has been a primary fixture in the line ever since.

The Patriots signed Koppen to a five-year, $20 million contract extension in 2006, which will keep him in New England through the 2011 season. He was selected to his first Pro Bowl in 2007 after helping the Patriots complete an undefeated regular season.

Koppen was the anchor of the line last season, and Bill Belichick will rely on him to have another strong year in 2010, especially with the the futures of Light and Mankins still up in the air.

Stephen Neal (right guard)

Stephen Neal was signed by the Patriots in 2001, but didn’t get a chance to start until 2004. Like Koppen, Neal has been a big part of the Pats offensive line for a long time, and doesn’t appear to be going anywhere anytime soon. The 33-year-old veteran signed a new two-year contract this past March.

Nick Kaczur (right tackle)

The original plan coming into the 2010 season was for Nick Kaczur to battle Sebastian Vollmer for the starting right tackle position. However, with Mankins absent, Kaczur has filled in at left guard during this Spring’s OTAs. Thus, it appears the team is ready to move on without Mankins, and experiment with moving guys around.

“We’ve worked players at every position,” coach Bill Belichick said. “We have multiple players playing every spot. It’s that time of year. We have a full roster. Nothing really new about that.”

The Road Ahead

It now appears the Patriots won’t be able to afford to let go of Matt Light this offseason. With Mankins on the way out, there will be some new faces stepping into starting roles, as well as some familiar faces filling in at new positions. It will be interesting to see if this unit can rebound from what has thus far been a fairly tumultuous offseason, and remain one of the top offensive lines in the NFL in 2010. All of the lineman know that they’ll need to be ready to play other positions, and do what is necessary to help the team win, even the inexperienced Connolly.

“You want to be able to be as valuable to the team as possible, so know as much as you can is the way to go,” Connolly said. “To know every position, and if they call on me to play something, I have to be ready.”